Internal combustion engine



Sept. 8, 1931. H. LE v. HORNING 1,822,097

INTERNAL OMBUSTION ENGINE Original Filed Nov. 13, 1916.

Patented Sept.I 8, 1931 UNITED STATES PATENT, OFFICE HARRY IIE-VAN HORNING, F WAUKESHA, WISCONSIN INTERNAL coMBusrIoN ENGINE f Application led November 13, 19116, Serial No. 130,965. Renewed April 23, 1926.

My invention relates to internal combustion engines, and its object is to provide an improved construction llooking toward the elimination of hot spots in the cylinders,

which frequently cause pre-ignition, and

which make for the deterioration ofthe structure. The present invention relates particularly to the spark plug construction and it will be seen that I not only eliminate hot 1o spots which are harmful so far as pre-ignition is concerned, but I also preserve the insulating body of porcelain, for instance, of the spark plug. In the prior art structures the spark plug comprises a main metallic body which ordinarily is threaded into the spark plug receiving ring, which, in turn, is threaded into the engine cylinder. This structure presents two difficulties. One diiiculty lies in the resulting hot spots. The

2t threaded joints are poor conductors of heat Y and the smaller masses therefore become heated to an excessive degree. diiiiculty proceeds from the fact that the heat is not conducted away from the porcelain efficiently and the porcelain becomes cracked and disintegrated very quickly. The lov-.f heat conducting efficiency of the threaded joints may be illustrated by screwing a bolt into a solid body and then heating the whole to a red glow. In the process of cooling the bolt will glow long after the' body is cooled.

According to myv invention I mount the porcelain of the spark plug directly in a properly formed opening '1n the cylinder head, the cylinder head being. cooled by a water jacket in the usual manner. I also provide means for securing the porcelain in the cylinder head in such a way as to secure heat conduction of great .eiliciency and accordingly hot spots are avoided and the p0rcelain is preventedfrom being heated to a harmful degree.

I shall now describe my invention in detail by reference to the accompanying drawin in which gure 1 is a cross-sectional view of an internal combustion engine embodying the feai tures of my invention;

Figure 2 is an enlarged view of the spark plug structure;

The other` Figure 3 shows a modification;

Figure 4 shows another modification; and

Figure 5 shows still another modification.

Referring first to Figure 1 it Will be seen that the engine is provided with the crank case 6 in which the crank shaft 7 is mounted.

plete the ordinary circulating system. The` particular view happens to show the exhaust valve 15 which is operated from the camshaft 16, this valve controlling the exhaust port 17 leading to the exhaust manifold 18 in 7o the usual manner.

The spark plug is provided in the cylinder head and the arrangement is shown in detail in Figure 2. .It will be seen that the cylinder head is provided with a spark plug opening 19 which has a shoulder 20. A gasket 21 of some such material as'copper asbestos is laid upon the shoulder 20 and the porcelain 22, havingthe fiange 23, is laid upon this gasket, as shown. On top of the flange 23,

there is provided another gasket of some such material ascopper asbestos, indicated at 24, anda clamping ring 25 threaded directly in the cylinder head, as shown, is screwed down *on top of the gasket 24, as shown, with a main 85 .cooling space between the ring 25 and the porcelain. The electrode 26 is mounted iny the porcelain22 in the usual manner, bein provided with the connecting terminal at the upper end thereof. The electrode 26 90 is placed in proper juxtaposition to the cylinder vformations 28v whlch constitute the other terminal of the spark gap, the circular face of flange 23 acting as a guide and formations 28 being grounded in the usual way in 95 order to form part of the ignition circuit. In this way the porcelain 22 is disposed directly in the cylinder head without the employment of any intervening parts. The

porcelain is so disposed in the cylinder head that the heat therein may readily pass to the larger mass Without the interference of obstructions such as poor joints. It will be clear that it is not necessary that the porcelain 22 be held in position in the precise manner shown, it being entirely practical to use a flange ring bolted down on top of the cylinder and extending down on top of the gasket 24, instead of the threaded gland nut shown.

The structure illustrated in Fig. 3 is like that illustrated in Fig. 2 except that the spark plug itself is provided with two electrodes 29 and 29', the cylinder formations 28 of Fig. 2 being then entirely omitted. In this case there are two connecting terminals 30 and 30 on the spark plug itself.

The structure illustrated in Fig. 4 is like that of Fig. 2 except that the gland nut 31, which is employed instead of the gland nut 25, is cnt back, as illustrated at 32 in order to make room for a stuffing of some compressible material 33 of high heat conducting quality, such as tin. the idea being to provide a large heat conducting` contact area for the porcelain and also, for such area, an intimatecontact.

The structure illustrated in Fig. 5 is like that of Fig. 4 except that the gasket 24 is omitted and the stuffing 34is so formed as to fill the entire space under the. gland nut 3l. It will be seen that this stuffing secures the proper seal and at the same time provides a considerable contact area for conducting heat awav from the porcelain, and with a very intimate contact. The parts being disposed directly in the cylinder head, the conduction of the heat is direct and effective and the advantages hereinbetore set forth are obtained simultaneouslyw'ith an advantageous simplification of structure.

I claim:

1. In an internal combustion engine. a,"

cylinder. an onening in the head of said cylinder. an insulating body set directly in said opening. a. clamping ring threaded directly in said cylinder head and retaining said body in said opening. a filling of tin between said body. said ring and said cylinder head. and a spark gap electrode mounted in said body.

2. In an internal combustion engine. a cvlinder. an opening in the. head of said cylinder. an insulating body set direetlvin said opening. means for clamping said body inV said opening. a filling of tin hetweeen said bodv. said ring and sai'd cylinder head. and a spark gan elect-rode mounted in said body.

3. In an internal combustion engine. a cylinder having an opening in the head thereof,

a Water iacket in said head surrounding and in close proximity to said opening. said opening having an outwardly facing shoul- .der therein and being reduced at its inner and, an insula ing member comprising an HARRY LE-VAN HORNING. 

